Air conditioning system with refrigerant leak management

A method of controlling an air conditioning system, the method comprising:

• controlling an air conditioner with a controller;
• measuring, with a thermostat, a temperature of an air conditioning target space;
• changing, with the thermostat, a contact point to an ON state or an OFF state in accordance with a measurement result;
• managing, with the thermostat, input of a control signal to the controller that controls operation of a component of the air conditioner;
• connecting the thermostat and the controller with a connection line group including a compressor operation command communication line that controls a compressor of the air conditioner and a fan operation command communication line that controls an indoor fan of the air conditioner;
• controlling, with a relay, a conductive state or a cut-off state of at least one of the compressor operation command communication line and the fan operation command communication line;
• detecting, with a leakage detection sensor, refrigerant leakage from the air conditioner;
• outputting, with the leakage detection sensor, a signal that controls the relay;
• and
• heating the air conditioning target space with a heater that is disposed separately from the air conditioner, wherein
• the connection line group further includes a heating operation command communication line that controls the heater, and
• when the leakage detection sensor detects refrigerant leakage from the air conditioner, the relay switches the heating operation command communication line to either a conductive state or a cut-off state.